The People Who Can Stay Underwater For Seven Minutes

The world record for staying underwater without breathing is over 24 minutes. Most normal humans would begin to suffer brain damages after a mere three minutes without oxygen. However, there are experts out there that have trained their bodies to survive in the most harsh conditions possible. These are their secrets.

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It's a widely known fact that famous illusionist Harry Houdini could hold his breath for three minutes; this was the key to one of his tricks, the Chinese Water Torture Cell.

Houdini's record three minutes and 30 seconds of static apnea was held for a long time, but these days that number is easily achievable by nearly anyone that attempts it after a small amount of training.

These days, the world record for a static apnea breath-holding attempt is nearly 12 minutes. The unofficial record of 11 minutes and 54 seconds, held by free-diver Branko Petrovic, was set in Dubai in late 2014, and the officially sanctioned record is less than 20 seconds shorter.

Record attempts are governed by AIDA, the International Association for Development of Apnea. The word apnea comes from the Greek apnous -- meaning breathless -- and while you might know it from its association with sleeping disorders, it also refers to a range of records.

Static apnea is the simplest, and therefore thought of as the purest, manifestation of breath-holding as a sport. It can be attempted in a pool or bath or any body of water, and simply requires the attemptee to remain completely underwater with their respiratory tract immersed.

Other apnea disciplines include constant weight, where divers wear a giant monofin and descend into the deeps, holding a rope once they've reached a maximum depth -- 128 metres is the record -- and no limits, where divers use a weighted sled to descend hundreds of metres before using a gas-filled balloon to re-surface -- in 2012, Herbert Nitsch hit 253 metres in his record attempt.

There's also a version of static apnea, too, that pushes the human body to its absolute limits. In it, attemptees are allowed to breathe pure oxygen for up to 30 minutes before their record attempt, cramming oxygen into every blood cell at the maximum concentration possible -- without risking oxygen toxicity.

The world record for static apnea with pure oxygen pre-breathing is 24 minutes and 3.45 seconds. The record, set by professional free-diver Aleix Segura, is a full minute longer than Segura's previous record and more than a minute clear of any other recent attempt.

How To Supercharge Your Breathing

There are training routines for newbie divers and wannabe record holders to expand their lung capacity and increase the efficiency with which their bodies can consume oxygen and can pull it out of the air they breathe.

The major hurdle to overcome is actually a mental one. The human body feels the urge to breathe in and out from a build up of carbon dioxide in the body, rather than an absence of oxygen; if this feeling can be overcome, it's possible for a free-diver to stay underwater and maintain a sufficient level of oxygen in their body for a significantly longer time.

Physically, the body can be trained on both a long-term and an immediate basis to more efficiently load itself up with oxygen and survive longer during free-diving or an underwater record attempt. First, free-divers try something called static apnea -- the suspension of breathing while not moving, usually sitting on the bottom of a shallow pool.

Not moving conserves the body's stored oxygen more slowly without the exertion of muscles, and divers usually let their bodies hang limply, relaxed like a corpse, to supercharge this.

Dynamic apnea, though, is thought to be the best way to train your body to stay underwater for as long as possible while conserving oxygen and not breathing.

Dynamic training requires heavy weights to be attached to the diver's body while swimming back and forth in a pool; these weights will likely be used during a free-diving record attempt, too, so they're useful to get used to initially.

Divers aim to add enough weight to be neutrally buoyant -- that is, not sinking -- a certain distance underwater. Different record classes include the option for

When it comes to an actual record attempt, prior to an extended breath-hold, divers will run through a standard routine to draw as much fresh oxygen into their bloodstream as possible.

Usually this involves around a minute of regular breathing, two to three minutes of slow and deep breathing where the exhale is twice the length of the inhale (to relax the body and lower its heart rate) and finally five to 10 fast, deep breaths (to reduce lung and bloodstream CO2 and increase O2) followed by one complete breath out and in as deep as possible.

From there, it's a matter of training and absolute willpower to force your body to overcome its basic instincts -- and to survive underwater for as long as possible.

Illusionist and stunt performer Harry Houdini was famously capable of holding his breath for over three minutes. But today, competitive breath-hold divers can squeeze ten, fifteen, even twenty minutes out of a single lungful of air. How do these divers do it -- and how can you train to hold your breath for longer?